Great progress in molecular breeding of hybrid rice in CNHRRDC

Elite maintainer lines and restorer lines have been developed by genomic DNA transformation,Analyses of molecular markers, DNA sequences, and Southern blotting have revealed that high DNA polymorphism exists between new developed lines and its receptors, indicating that the special DNA fragment from distant relatives may be integrated into the genome of rice. And several combinations with the potential of super-high yield have been developed from these lines. Therefore, transformation of genomic DNA from distant relatives to the plant of a target receptor may open an avenue for breeding of super-hybrid rice.

Present Status, Problems and Prospects of Molecular Breeding of Cotton (Gossypium) with Resistance against Verticillium dahliae Kleb.

VerticiUium wilt is an important disease in cotton production, which seriously affects the production of cotton. The classification and pathogenesis of Yer-ticillium dahliae Kleb. , achievements in QTL mapping and molecular breeding were reviewed in the paper. Meanwhile, the current problems and future direction of resistance breeding against V. dahliae Kleb. were discussed so as to provide reference information for further research on resistance breeding against the pathogen.

Prospect of the QTL-qSB-9^(Tq) utilized in molecular breeding program of japonica rice against sheath blight

The major QTL-qSB-9^Tq conferring partial resistance to rice （Oryza sativa L.） sheath blight （Rhizoctonia solani Kvhn） has been verified on chromosome 9 of the indica rice cultivar, Teqing. In this study, the prospect of this QTL utilized in molecular breeding program of japonica rice for sheath blight resistance was investigated. Most of the japonica rice cultivars showed lower level of sheath blight resistance than the indica rice cultivars. At the corresponding site of qSB-9^Tq, nine typical japonica rice cultivars from different ecological regions or countries proved to possess the susceptible allele（s）. Introgression of qSB-9^Tq into these cultivars enhanced their resistance level by decreasing sheath blight score of 1.0 （0.5-1.3）, which indicated that qSB-9^Tq had a large potential in strengthening the resistance of japonica rice to sheath blight. The use of the three molecular markers, which were polymorphic between Teqing and many japonica rice cultivars, promotes the application of qSB-9^Tq in a concrete molecular breeding program.

Strategy for Use of Rice Blast Resistance Genes in Rice Molecular Breeding

Rice blast is one of the most destructive diseases affecting rice production worldwide.The development and rational use of resistant varieties has been the most effective and economical measure to control blast.In this review,we summarized the cloning and utilization of rice blast resistance genes,such as Pi1,Pi2,Pi9,Pi54,Pigm and Piz-t.We concluded that three main problems in the current breeding of rice blast resistance are:availability of few R(resistance)genes that confer resistance to both seedling and panicle blast,the resistance effect of pyramided lines is not the result of a simple accumulation of resistance spectrum,and only a few R genes have been successfully used for molecular breeding.Therefore,novel utilization strategies for rice blast R genes in molecular breeding were proposed,such as accurately understanding the utilization of R genes in main modern rice varieties,creating a core resistant germplasm with excellent comprehensive traits,screening and utilizing broadspectrum and durable resistance gene combinations.Lastly,the trends and possible development direction of blast resistance improvement were also discussed,including new genes regulating resistance identified via GWAS(genome-wide association study)and improving rice blast resistance using genetic editing.

Red fluorescent protein (DsRed2), an ideal reporter for cotton genetic transformation and molecular breeding

Genes encoding reporter proteins are used as visual marker-assisted tools in genetic transformation as well as plant breeding. In this study, the red fluorescent protein identified in Discosoma sp. coral(DsRed2) was successfully used as a visual marker for cotton genetic engineering. DsRed2 was successfully expressed in two cotton cultivars,JIN668 and YZ1, driven by the Ca MV-35 S promoter via the Agrobacterium-mediated transformation. Our results suggest that DsRed2 expression provides an early-stage selection tool for the transgenic calli via visual observation. Red fluorescence can be detected not only in callus and somatic embryos but also in most tissues and organs of mature plants. The transgenic line Yz-2-DsRed2 was crossed with four different cotton cultivars to assess the transgene heritability and stability in different genetic backgrounds.The heritability of the red color was highly stable when Yz-2-DsRed2 was used as a male parent. The DsRed2 gene expressed 100% in the F_1 hybrids. To investigate the relationship between DsRed2 transcription and DNA methylation, a methylation-specific PCR approach was applied to the Ca MV-35 S promoter region. The results showed a negative association between DNA methylation level in the promoter region and the transgene transcription.Taken together, these findings suggest DsRed2 a visual reporter gene for cotton genetic transformation and molecular breeding programs.

Molecular breeding of hybrid rice

This paper describes in a general way the objectives, contents and methods of molecular breeding, and the application of molecular breeding in hybrid rice.

The story of a decade:Genomics,functional genomics,and molecular breeding in Brassica napus

Rapeseed(Brassica napus L.)is one of the major global sources of edible vegetable oil and is also used as a feed and pioneer crop and for sightseeing and industrial purposes.Improvements in genome sequencing and molecular marker technology have fueled a boom in functional genomic studies of major agronomic characters such as yield,quality,flowering time,and stress resistance.Moreover,introgression and pyra-miding of key functional genes have greatly accelerated the genetic improvement of important traits.Here we summarize recent progress in rapeseed genomics and genetics,and we discuss effective molecular breeding strategies by exploring thesefindings in rapeseed.These insights will extend our understanding of the molecular mechanisms and regulatory networks underlying agronomic traits and facilitate the breeding process,ultimately contributing to more sustainable agriculture throughout the world.

Molecular breeding of farm animals through gene editing

The rapid development of biotechnology has facilitated our understanding of the biological functions of candidate genes for important economic traits in farm animals.Molecular breeding by gene editing has greatly revolutionized the breeding of farm animals.Through gene editing and embryo manipulation,breeds with designed economic or disease-resistant traits can be readily generated.Along with this fast progress,the safety assessment of gene-edited farm animals has attracted public and regulatory attention.This review summarizes the research progress of gene editing in farm animals,focusing on performance improvement,disease resistance,bioreactors,animal welfare,and environmental friendliness.The limitations and future development of gene editing technology in farm animal breeding are also discussed.

Rice Heat Tolerance Breeding: A Comprehensive Review and Forward Gaze

The yield potential of rice is seriously affected by heat stress due to climate change. Since rice is a staple food globally, it is imperative to develop heat-resistant rice varieties. Thus, a thorough understanding of the complex molecular mechanisms underlying heat tolerance and the impact of high temperatures on various critical stages of the crop is needed. Adoption of both conventional and innovative breeding strategies offers a long-term advantage over other methods, such as agronomic practices, to counter heat stress. In this review, we summarize the effects of heat stress, regulatory pathways for heat tolerance, phenotyping strategies, and various breeding methods available for developing heat-tolerant rice. We offer perspectives and knowledge to guide future research endeavors aimed at enhancing the ability of rice to withstand heat stress and ultimately benefit humanity.

Advances in Understanding Cadmium Stress and Breeding of Cadmium-Tolerant Crops

Cadmium(Cd) pollution has emerged as a critical global environmental concern, due to its significant toxicity, environmental persistence, and the pervasiveness of contamination. Significantly, the bioaccumulation of Cd in agricultural crops constitutes a primary vector for its entry into the human diet. This issue warrants urgent attention from both the scientific community and policymakers to develop and implement effective mitigation strategies. This review delves into the physiological impacts of Cd stress on plants, including the suppression of photosynthetic activity, amplification of oxidative stress, and disruptions in mineral nutrient homeostasis. Additionally, the resistance mechanisms deployed by plants in response to Cd stress have been explored, and the prospective contributions of molecular breeding strategies in augmenting crop tolerance to Cd and minimizing its bioaccumulation have been assessed. By integrating and analyzing these findings, we seek to inform future research trajectories and proffer strategic approaches to enhance agricultural sustainability, safeguard human health, and protect environmental integrity.

A High-Density SNP Genotyping Array for Rice Biology and Molecular Breeding

A high-density single nucleotide polymorphism （SNP） array is critically important for geneticists and molecu- lar breeders. With the accumulation of huge amounts of genomic re-sequencing data and available technologies for accurate SNP detection, it is possible to design high-density and high-quality rice SNP arrays. Here we report the devel- opment of a high-density rice SNP array and its utility. SNP probes were designed by screening more than 10 000 000 SNP loci extracted from the re-sequencing data of 801 rice varieties and an array named RiceSNP50 was produced on the Illumina Infinium platform. The array contained 51 478 evenly distributed markers, 68% of which were within genic regions. Several hundred rice plants with parent/F1 relationships were used to generate a high-quality cluster file for accurate SNP calling. Application tests showed that this array had high genotyping accuracy, and could be used for dif- ferent objectives. For example, a core collection of elite rice varieties was clustered with fine resolution. Genome-wide association studies （GWAS） analysis correctly identified a characterized QTL. Further, this array was successfully used for variety verification and trait introgression. As an accurate high-throughput genotyping tool, RiceSNP50 will play an important role in both functional genomics studies and molecular breeding.

Genetic and genomic analyses for economically important traits and their applications in molecular breeding of cultured fish

The traits of cultured fish must continually be genetically improved to supply high-quality animal protein for human consumption.Economically important fish traits are controlled by multiple gene quantitative trait loci(QTL),most of which have minor effects,but a few genes may have major effects useful for molecular breeding.In this review,we chose relevant studies on some of the most intensively cultured fish and concisely summarize progress on identifying and verifying QTLs for such traits as growth,disease and stress resistance and sex in recent decades.The potential applications of these major-effect genes and their associated markers in marker-assisted selection and molecular breeding,as well as future research directions are also discussed.These genetic and genomic analyses will be valuable for elucidating the mechanisms modulating economically important traits and to establish more effective molecular breeding techniques in fish.

Recent Progress Using High-throughput Sequencing Technologies in Plant Molecular Breeding

High-throughput sequencing is a revolutionary technological in- novation in DNA sequencing. This technology has an ultra-low cost per base of sequencing and an overwhelmingly high data output. High-throughput sequencing has brought novel research methods and solutions to the research fields of genomics and post-genomics. Furthermore, this technology is leading to a new molecular breeding revolution that has landmark significance for scientific research and enables us to launch multi-level, multi- faceted, and multi-extent studies in the fields of crop genetics, genomics, and crop breeding. In this paper, we review progress in the application of high-throughput sequencing technologies to plant molecular breeding studies.

From Basic Research to Molecular Breeding——Chinese Scientists Play A Central Role in Boosting World Rice Production

On November 18, 2018, the Future Science Prize Awarding Ceremony was held in Beijing. In the area of life science, Professors Jiayang Li, Longping Yuan, and Qifa Zhang shared the prize for their pioneering contributions in producing high-yield, superior-quality rice through systematic study of molecular mechanisms associated with speci?c rice features and application of novel approaches in rice breeding. The Future Science Prize is also touted as ‘‘China’s Nobel Prize", fully af?rming their achievements in rice basic research and breeding.

Rice3K56 is a high-quality SNP array for genome-based genetic studies and breeding in rice(Oryza sativa L.)

Single nucleotide polymorphism(SNP)genotyping arrays provide an optimal high-throughput platform for genetic research and molecular breeding programs in both animals and plants.In this study,a highquality and custom-designed Rice3K56 SNP array was developed with the resequencing data of 3024 rice accessions worldwide,which was then tested extensively in 192 representative rice samples.Printed on the Gene Titan chips of Affymetrix Axiom each containing 56,606 SNP markers,the Rice3K56 array has a high genotyping reliability(99.6%),high and uniform genome coverage(an average of 6.7-kb between adjacent SNPs),abundant polymorphic information and easy automation,compared with previously developed rice SNP arrays.When applied in rice varietal differentiation,population diversity analysis,gene mapping of 13 complex traits by a genome-wide association study analysis(GWAS),and genome selection experiments in a recombinant inbred line and a multi-parent advanced generation inter-cross populations,these properties of the Rice3K56 array were well demonstrated for its power and great potential to be a highly efficient tool for rice genetic research and genomic breeding.

Tree Genetics and Molecular Breeding(TGMB)

Tree Genetics and Molecular Breeding(ISSN 1927-5781)is an international,open access,peer reviewed journal,committed to serve for tree genetics and molecular breeding,particularly publishing innovative research findings in the basic and applied fields of tree molecular genetics and novel techniques for fruit/forest/ornamental/

Animal Molecular Breeding(AMB)

Animal Molecular Breeding(ISSN 1927-5609)is an open access,peer reviewed journal published online by Bio Publisher.The journal is publishing all the latest and outstanding research articles,letters and reviews in all areas of animal molecular breeding,containing transgenic breeding and marker assisted breeding,particularly publishing innovative

Animal Molecular Breeding(AMB)

Animal Molecular Breeding(ISSN 1927-5609)is an open access,peer reviewed journal published online by Bio Publisher.The journal is publishing all the latest and outstanding research articles,letters and reviews in all areas of animal molecular breeding,containing transgenic breeding and marker assisted breeding,

Genetic study and molecular breeding for high phosphorus use efficiency in maize

Phosphorus is the second most important macronutrient after nitrogen and it has many vital functions in the life of plants.Most soils have a low available P content,which has become a key limiting factor for increasing crop production.Also,low P use efficiency(PUE)of crops in conjunction with excessive application of P fertilizers has resulted in serious environmental problems.Thus,dissecting the genetic architecture of crop PUE,mining related quantitative trait loci(QTL)and using molecular breeding methods to improve high PUE germplasm are of great significance and serve as an efficient approach for the development of sustainable agriculture.In this review,molecular and phenotypic characteristics of maize inbred lines with high PUE,related QTL and genes as well as low-P responses are summarized.Based on this,a breeding strategy applying genomic selection as the core,and integrating the existing genetic information and molecular breeding techniques is proposed for breeding high PUE maize inbred lines and hybrids.